A solar cell may be defined as a device for converting light energy into electric energy by using a photovoltaic effect where electrons are produced by exposing a p-n junction diode to light. Such solar cells may be classified into a silicon solar cell, a compound semiconductor solar cell, a dye-sensitized solar cell, and an organic solar cell according to a material used as a junction diode.
A minimum unit of a solar cell is a cell, and a voltage produced by one solar cell is generally as low as approximately 0.5 V to 0.6 V. A unit fabricated in the form of a panel where several solar cells are connected to each other in series on a substrate to produce a voltage of several volts or several hundred volts is referred to as a module, and a solar cell apparatus is fabricated by installing the solar cell module on a frame.
In the solar cell apparatus, conductors (bus bars) serving as a positive electrode and a negative electrode are connected to the solar cells. In a general bus bar fabricating process, after a solar cell module is fabricated, a metal bus bar is formed on a solar cell module through a process such as soldering. Next, a bonding member having a color similar to that of an external panel is disposed on the bus bar to improve an outer appearance of the solar cell module.
The bus bar fabricated through the method has a weak bonding strength to the solar cell module, and also requires an additional process for improving an outer appearance of the solar cell module, deteriorating process efficiency.